A PRIZE ESSAY. 
53 
SECTION XIII. 
MANURES COMPOSED CHIEFLY OF MOULD, 
These are of vegetable or animal origin. And 
first, of animal mould. Here we shall find that we 
come, perhaps, better prepared to understand this 
part of our subject, than either of the preceding 
classes. We have explained the principles which en¬ 
able us to understand why it is that animal and vege¬ 
table substances produce, by decay, identical matters. 
The only difference consists in the quantity of these 
matters. 
Let me here, reader, call to your remembrance the 
facts we stated respecting the two classes of food, and 
the two classes of substances formed from that food 
by animals. A certain portion of that food contains 
none of that principle which forms ammonia. This 
portion of food makes fat. Another portion of food 
contains the substance which forms ammonia. This 
part of the food forms flesh and blood, and the other 
parts of the body, skin, hair, feathers, bristles, wool, 
horns, hoofs, nails and claws, thews and sinews. Now, 
when a body dies and decays, the mould which it 
forms will be rich manure, or poor manure, just in 
proportion asdt contains more or less of the substances 
formed out of that portion of food which furnishes 
flesh and blood. The fat, therefore, in animal mould, 
plays a very inferior part to that acted by the flesh 
and blood. In a word, as I wish to dismiss the fatty 
matters from our present consideration, I may do this, 
reader, by stating to you all that you need know, that 
in decay, fat forms chiefly carbonic acid. If, therefore, 
you call to mind what we have said about the action 
of that, you will see how fat acts in manure. But the 
flesh and blood, and the substances formed from it, 
give precisely the same things as vegetables do when 
they decay ; that is, water, mould, and salts. 
